The present invention relates to an arrangement for introducing a bulk material into a vessel, particularly a combustible particulate material into a pressurized gasifying vessel, and to a method of operating such an arrangement.
Attempts have already been made to gasify combustible particulate materials, the particulate sizes of which may range from small granules to dust-like consistency. In particular, it has been already attempted to so gasify, for instance, coaldust, which is otherwise a very difficult substance to burn by traditional methods. Such gasification is usually performed at high pressures, such as, for instance, 25 atm. above the atmospheric pressure and in the presence of oxygen or oxygen-containing gaseous media, whereby partial oxidation is achieved. When such considerable pressure is to be employed, the arrangement for introducing the particulate material into the gasifying vessel, such as a lock-type arrangement, must be so constructed and dimensioned as to be able to withstand such high pressures and pressure differentials, so that such arrangements are rather complex, expensive and prone to malfunction.
Experience has shown, however, that when the gaseous medium obtained during the partial oxidation is to be used immediately and/or in the immediate vicinity of the gasifying device, a situation may arise in which a relatively low pressure is needed in the gasifying space in order to obtain a gas which can be used to advantage. Various computations have been made in this connection with the result that it is sufficient, under such circumstances, to operate the gasifying arrangement at a pressure of 5 atm. superatmospheric pressure maximum, at which pressure the gaseous medium will also be discharged from the gasifying space.